My first commit of codes

vendor/psy/psysh/test/tools/vis.py

@@ -0,0 +1,126 @@
+"""
+vis.py
+======
+
+Ctypes based module to access libbsd's strvis & strunvis functions.
+
+The `vis` function is the equivalent of strvis.
+The `unvis` function is the equivalent of strunvis.
+All functions accept unicode string as input and return a unicode string.
+
+Constants:
+----------
+
+* to select alternate encoding format
+  `VIS_OCTAL`:      use octal \ddd format
+  `VIS_CSTYLE`:     use \[nrft0..] where appropiate
+
+* to alter set of characters encoded
+  (default is to encode all non-graphic except space, tab, and newline).
+  `VIS_SP`:         also encode space
+  `VIS_TAB`:        also encode tab
+  `VIS_NL`:         also encode newline
+  `VIS_WHITE`:      same as (VIS_SP | VIS_TAB | VIS_NL)
+  `VIS_SAFE`:       only encode "unsafe" characters
+
+* other
+  `VIS_NOSLASH`:    inhibit printing '\'
+  `VIS_HTTP1808`:   http-style escape % hex hex
+  `VIS_HTTPSTYLE`:  http-style escape % hex hex
+  `VIS_MIMESTYLE`:  mime-style escape = HEX HEX
+  `VIS_HTTP1866`:   http-style &#num; or &string;
+  `VIS_NOESCAPE`:   don't decode `\'
+  `VIS_GLOB`:       encode glob(3) magic characters
+
+:Authors:
+    - ju1ius (http://github.com/ju1ius)
+:Version: 1
+:Date: 2014-01-05
+"""
+from ctypes import CDLL, c_char_p, c_int
+from ctypes.util import find_library
+
+
+__all__ = [
+    'vis', 'unvis',
+    'VIS_OCTAL', 'VIS_CSTYLE',
+    'VIS_SP', 'VIS_TAB', 'VIS_NL', 'VIS_WHITE', 'VIS_SAFE',
+    'VIS_NOSLASH', 'VIS_HTTP1808', 'VIS_HTTPSTYLE', 'VIS_MIMESTYLE',
+    'VIS_HTTP1866', 'VIS_NOESCAPE', 'VIS_GLOB'
+]
+
+
+#############################################################
+# Constants from bsd/vis.h
+#############################################################
+
+#to select alternate encoding format
+VIS_OCTAL = 0x0001
+VIS_CSTYLE = 0x0002
+# to alter set of characters encoded
+# (default is to encode all non-graphic except space, tab, and newline).
+VIS_SP = 0x0004
+VIS_TAB = 0x0008
+VIS_NL = 0x0010
+VIS_WHITE = VIS_SP | VIS_TAB | VIS_NL
+VIS_SAFE = 0x0020
+# other
+VIS_NOSLASH = 0x0040
+VIS_HTTP1808 = 0x0080
+VIS_HTTPSTYLE = 0x0080
+VIS_MIMESTYLE = 0x0100
+VIS_HTTP1866 = 0x0200
+VIS_NOESCAPE = 0x0400
+VIS_GLOB = 0x1000
+
+#############################################################
+# Import libbsd/vis functions
+#############################################################
+
+_libbsd = CDLL(find_library('bsd'))
+
+_strvis = _libbsd.strvis
+_strvis.argtypes = [c_char_p, c_char_p, c_int]
+_strvis.restype = c_int
+
+_strunvis = _libbsd.strunvis
+_strvis.argtypes = [c_char_p, c_char_p]
+_strvis.restype = c_int
+
+
+def vis(src, flags=VIS_WHITE):
+    """
+    Encodes the string `src` into libbsd's vis encoding.
+    `flags` must be one of the VIS_* constants
+
+    C definition:
+    int strvis(char *dst, char *src, int flags);
+    """
+    src = bytes(src, 'utf-8')
+    dst_p = c_char_p(bytes(len(src) * 4))
+    src_p = c_char_p(src)
+    flags = c_int(flags)
+
+    bytes_written = _strvis(dst_p, src_p, flags)
+    if -1 == bytes_written:
+        raise RuntimeError('vis failed to encode string "{}"'.format(src))
+
+    return dst_p.value.decode('utf-8')
+
+
+def unvis(src):
+    """
+    Decodes a string encoded by vis.
+
+    C definition:
+    int strunvis(char *dst, char *src);
+    """
+    src = bytes(src, 'utf-8')
+    dst_p = c_char_p(bytes(len(src)))
+    src_p = c_char_p(src)
+
+    bytes_written = _strunvis(dst_p, src_p)
+    if -1 == bytes_written:
+        raise RuntimeError('unvis failed to decode string "{}"'.format(src))
+
+    return dst_p.value.decode('utf-8')